I know a bunch of FT flyers are committed to their rollaboards but I'd respectfully suggest working to fit one's carryon as either a backpack or a soft-sided duffle or a larger computer/briefcase bag with strap as your standard travel gear and eliminate a rollaboard as a carryon.

As soon as a lazy GA sees a rollaboard and decides to call "full", you're hosed. Period.

On RJs and limited sized overhead cabins, there's always a food fight for space - particularly with the rollaboards.

David